Velocity responsive actuating means



Jan. 17, 1967 G. DE COYE DE CASTELET 3,299,234

VELOCITY RESPONSIVE ACTUATING MEANS Filed June 7, 1965 Invenar GAG kart Decoye De CaSlG/QZ RH-ornu/s United States Patent VELGCITY RESPONSIVE ACTUATING MEANS Gatan de Coye de Castelet, Billancourt, France, assignor to Regie Nationale des Usines Renault, Billancourt,

France, a French works Filed June 7, 1965, Ser. No. 461,906 Claims priority, application France, July 22, 1964, 982,641, Patent 1,409,877 9 Claims. (Cl. 20061.45)

Tachometric contactors are already known wherein the contact making and breaking members consist of flexible metal blades having substantially an S-shaped curvature, these blades being disposed between end bearings and adapted to either abruptly engage or snappily move away from contacts by undergoing a slight deformation under the influence of a member providing to this end a static effort as a function of the velocity of motion of a movable body or unit.

A contactor of this general type is disclosed in the French Patent No. 1,271,126 of July 25, 1960 in the name of Etablissements Ed. Jaeger and entiled Tachometric Contactor. According to this prior patent, the member producing said static effort is a magnet revolving within a metal bell-shaped member which it tends to carry along, by means of the eddy currents induced therein, against the resistance of spring means of which the degree of elongation determines the engagement of each S-shaped blade against one or the other of its contacts. Moreover, the limit torque values of said bell-shaped member, which control the contact changes of each blade (and therefore the limit speeds of the rotating magnet) diifer according to which of the contacts said blade is to separate from, and the values of these limit torques may be adjusted by varying the position of the anchor point of the spring concerned.

A contactor of this character may advantageously be used for controlling gear changes in an automotive vehicle. In this case, the limit torque adjustment may be made responsive to the means controlling the engine power output.

T achometric contactor control devices are also known wherein the control action by magnet or metal bell is adjustable by altering the relative axial spacing of the magnet and bell, as disclosed in the patent application Ser. No. 439,285 filed on Mar. 12, 1965 by the same applicant.

It is the essential object of the present invention to provide improvements in or relating to existing devices of this character which consist notably in that the discrepancies between the limit values of the torques actuating said S-shaped blades are adjusted by members adapted to alter the position of at least one of the side contacts of each blade as a function of a parameter which, for example in the case of an automotive vehicle, may be the position of the accelerator pedal.

This member may be for example an electromagnet, a hydraulic or pneumatic cylinder, or even a simple mechanical linkage associating the positions of said contacts with the position of said pedal.

In order to afford a clearer understanding of the present invention and of the manner in which the same may carried out in practice, reference will now be made to the accompanying drawing illustrating diagrammatically by way of example a typical form of embodiment of this invention. In the drawing:

FIGURE 1 is an axial section showing a device for producing a static torque by using a rotary magnet and a metal bell-shaped member;

FIGURE 2 is a diagram showing a typical mounting of an S-shaped blade;

FIGURE 3 is another diagram showing a typical adjustment of the contacts of an S-shaped blade;

FIGURE 4 is a modified form of embodiment of the preceding mounting, and

FIGURE 5 is a diagram showing a two-blade contactor.

A contactor according to this invention comprises essentially in a same casing a tachometric control member, a number of switches of the S-shaped blade type, and means for adjusting the contacts of said switches.

The tachometric control member (see FIGURE 1) may consist for example of a permanent magnet A mounted in a bearing rigid with the casing G and revolving within a hell-shaped metal member C. The magnet A is rotatably driven through a flexible cable F from the power take off provided for example on the output shaft of the transmission of an automotive vehicle. This magnet revolves in a metal bell C and tends to carry along this bell by introducing eddy currents into it, this bell being on the other hand retained by a torsion or like spring r attached to a bar P.

A switch unit (see FIGURE 2) comprises an S-shaped blade S clamped between two end bearings K, K and adapted to engage one or the other of a pair of contacts B and B.

The blade S moves snappily from one to the other of these contacts as a consequence of the deformation of the blade S responsive to the bar P.

- As clearly shown in FIGURE 2 the blade S is attached at X on the one hand to said bar P through a connecting rod, and on the other hand to a traction spring R counteracting the pulling of this blade S by the bar P.

Due to the torque effect created by the rotation of the magnet A in the bell C, the bar P tends to elongate the spring R by moving the blade S from its position shown in full lines in the figure to a position S shown in dash lines.

When this torque decreases (as will occur when the magnet speed decreases the force of spring R becomes preponderant and the flexible blade S resumes its initial position S.

In this initial position, if f is the force exerted by the blade against its contact B, and f the tension of spring R, the force F necessary to enable the bar P to switch the blade from B to B is:

When the blade is :at B, it exerts on this point a force f equal to or other than f but of opposite direction, so that the lower limit force F below which the tractive effort exerted by the bar P on spring R must fall to enable the blade S to resume its initial position at B will be:

assuming, of course, that the value of f is the same in both Equations 1 and 2 which is actually the case with :a sufficient approximation, provided that spring R has a sufficient length.

It will be seen that under these conditions F F.

Assuming that B is a back contact and B a front contact of a switch comprised of these two contacts and blade S, for example in a mounting controlling the energization of the coil of a change-speed relay RA (not shown in the drawing), it will be seen that the limit force F required for triggering the switch is greater than the limit force F necessary for releasing same. This provides for a certain stability in said gear change.

In order to provide for the adjustment of this stability, the present invention .provides means for adjusting the position of at least one of contacts B and B.

In a certain position of the S blade between its bearings the forces f and f are zero; this is the so-called neutral line. To move the S blades away from this 3 neutral line will considerably alter the state of equilibrium between F or F and f whereby the aforesaid stability may be eliminated nearly completely.

In the alternate form of embodiment shown diagrammatically in FIGURE 3 it is the front contact B that is made movable by mounting sameon an arm I rigid' with a lever L fulcrumed on a pivot pin Y. The travel of lever L is limited by stop H.

In this specified form of embodiment the lever L consists of magnetic material and constitutes the armature of an elect-romagnet E having its coil energized from a source of current U through a control member V. This control member V may be a simple ON-OFF switch, or a known device for the continuous adjustment of the energizing current fed to B (such as a rheostat or a variable inductance).

This member may be actuated for example by depressing the accelerator pedal by mean of a rod D.

As an alternative (see FIGURE 4) the front contact B is mounted on an elastic rod J adapted to be deflected by a stop B carried by'a lever i.

A tachometric contactor according to this invention may be used for controlling gear changes in an automotive vehicle. The two-blade device shown in FIGURE comprises a single tachometric control member of which the bar -P is adapted to tension both springs R and R simultaneously. I

In this specific form of embodiment the first blade S may be used, for example, for controlling up and down gear shifts between low speed and intermediate speed, blade S controlling up and down gear shifts between intermediate speed and top speed. Contact B of blade S is shown with the adjustment means of FIGURE 4, and contact B' of blade S corresponds to the mounting of FIGURE 3. As contrasted with FIGURE 3, the change-speed relay RA shown in FIGURE 5 is responsive to the back contact B this arrangement being preferred in practice because it avoids the passage of current through the movable lever L Moreover, the member V controlling blade S is actuated in conjunction with the control member V of S These control members may be responsive for example to the accelerator pedal beyond its normal stroke after clearing a mechanical resistance. The movement of front contact 3' and B' beyond the intermediate neutral line wherein the S blade is in a position of unstable equilibrium, will accelerate a down change to a lower gear, thus permitting a more sports-like driving. According as the driver regulates or not the aforesaid members V and V he has at his disposal either an adjustment means capable of imparting the maximum responsiveness to the vehicle or on the contrary a more stable adjustment means reducing the number of gear shifts.

The successive changes in the position of blades S and S will mutually react on their conditions of release. Therefore, adjustments should be made on the fully mounted device.

1 claim:

1. A velocity responsive actuating means for use in the gear shift control means of, for example, an automotive vehicle which includes an engine and an accelerator pedal for controlling the velocity output thereof, said means comprising: a, rotating member, an actuating means which is movable in response to the velocity of said rotating member, a switch means comprising a flexible S-shaped metal blade flexibly snapable to either side of a neutral axis, said blade being mounted at its ends in fixed bearings, a contact on each side of said blade at a location intermediate its ends, said actuating means being connected to said blade and urging it towards one of said contacts, a yieldable means urging said blade towards the other of said contacts, said blade resting against one or the other of said contacts depending upon the velocity of said rotating member and the consequent force exerted by said velocity responsive actuating means upon said blade, and adjustment means actuable by said accelerator pedal to adjustably move one of said contacts laterally relative to said blade.

2. The tachometric contactor of claim 1, wherein said adjustment means comprises a pivoted lever, said one of said contacts being movable in response to pivoting of said pivoted lever, means to adjustably pivot said lever.

3. The tachometric contactor of claim 2, said last men tioned means including an electrommagnet, said lever constituting the armature of said electromagnet.

4. The tachometric contactor of claim 2, wherein said one contact is integrally mounted on said lever.

5. The tachometric contactor of claim 2, wherein said one contact is movably mounted separately from said lever.

6. The tachometric contactor of claim 3, the energizing circuit of said electromagnet including a means to vary the energizing current to said electromagnet.

7. The tachometric contactor of claim '6, wherein said last mentioned means comprises a simple on-off switch.

8. The tachometric contactor or claim 3 adapted for use in an automotive gear shift having three gear shift ratios, said contactor comprising two of said S-shaped blades and a single said actuating means connected to both said blades, one of said blades and its associated said contacts being associated with a first and second of said gear ratios and the other of said blades being associated with the second and third of said gear ratios.

9. The tachometric contactor of claim 8, wherein the movable ones of said contacts are movable by the contact adjustment means to beyond the neutral axis of the blade in a direction towards the other of said contacts.

References Cited by the Examiner UNITED STATES PATENTS 1,668,974 5/1928 Mottlau 200-67 2,501,497 3/ 1950 Clark et al. 20067 2,512,306 6/ 1950 Clark et al. 200-67 2,880,288 3/1959 Rosenberg 2006l X BERNARD A. GILHEANY, Primary Examiner.

J, BAKER, A istant Examiner. 

1. A VELOCITY RESPONSIVE ACTUATING MEANS FOR USE IN THE GEAR SHIFT CONTROL MEANS OF, FOR EXAMPLE, AN AUTOMOTIVE VEHICLE WHICH INCLUDES AN ENGINE AND AN ACCELERATOR PEDAL FOR CONTROLLING THE VELOCITY OUTPUT THEREOF, SAID MEANS COMPRISING: A ROTATING MEMBER, AN ACTUATING MEANS WHICH IS MOVABLE IN RESPONSE TO THE VELOCITY OF SAID ROTATING MEMBER, A SWITCH MEANS COMPRISING A FLEXIBLE S-SHAPED METAL BLADE FLEXIBLY SNAPABLE TO EITHER SIDE OF A NEUTRAL AXIS, SAID BLADE BEING MOUNTED AT ITS ENDS IN FIXED BEARINGS, A CONTACT ON EACH SIDE OF SAID BLADE AT A LOCATION INTERMEDIATE ITS ENDS, SAID ACTUATING MEANS BEING CONNECTED TO SAID BLADE AND URGING IT TOWARDS ONE OF SAID CONTACTS, A YIELDABLE MEANS URGING IT TOWARDS ONE OF THE OTHER OF SAID CONTACTS, SAID BLADE RESTING AGAINST ONE OR THE OTHER OF SAID CONTACTS DEPENDING UPON THE VELOCITY OF SAID ROTATING MEMBER AND THE CONSEQUENT FORCE EXERTED BY SAID VELOCITY RESPONSIVE ACTUATING MEANS UPON SAID BLADE, AND ADJUSTMENT MEANS ACTUABLE BY SAID ACCELERATOR PEDAL TO ADJUSTABLY MOVE ONE OF SAID CONTACTS LATERALLY RELATIVE TO SAID BLADE. 